Catalyst for copolymerization of ethylene and methyl methacrylate, and application thereof

Abstract

The present application provides a catalyst for copolymerization of ethylene and methyl methacrylate and an application thereof. The catalyst includes a main catalyst, and the main catalyst is obtained by compounding a compound of formula (I) and a compound of formula (II); a mole ratio of the compound of formula (I) to the compound of formula (II) is (1:49) to (49:1). The catalyst has an excellent catalytic activity, and a copolymer of ethylene and methyl methacrylate with a high molecular weight can be obtained, with a weight average molecular weight of not less than 1×10 5 g/mol.

What is claimed is: 
     
         1 . A catalyst for copolymerization of ethylene and methyl methacrylate, wherein the catalyst comprises a main catalyst, and the main catalyst is obtained by compounding a compound of formula (I) and a compound of formula (II);
 a structure of the compound of formula (I) is:   
       
         
           
           
               
               
           
         
         wherein, R 1  and R 2  are each independently selected from substituted aryl, a substituent being selected from at least one of C1-C6 alkyl and C1-C6 alkoxy; 
         R 3  and R 4  are each independently selected from hydrogen and C1-C4 alkyl; 
         M is selected from Ni or Pd; 
         X 1  and X 2  are each independently selected from at least one of halogen, C1-C4 alkyl, aryl, C2-C4 ether and C1-C4 nitrile; 
         a structure of the compound of formula (II) is: 
       
       
         
           
           
               
               
           
         
         wherein, R 5  and R 6  are each independently selected from at least one of hydrogen, methyl, ethyl, dimethylamino, diethylamino, amino, hydroxyl, and C1-C4 alkoxy; 
         R 7  and R 8  are each independently selected from at least one of hydrogen, C1-C4 alkyl, C1-C4 dialkylamino, amino, hydroxyl, and C1-C4 alkoxy; 
         a mole ratio of the compound of formula (I) to the compound of formula (II) is (1:49) to (49:1). 
       
     
     
         2 . The catalyst according to  claim 1 , wherein the mole ratio of the compound of formula (I) to the compound of formula (II) is (1:10) to (10:1). 
     
     
         3 . The catalyst according to  claim 1 , wherein the catalyst further comprises a co-catalyst selected from aluminoxane. 
     
     
         4 . The catalyst according to  claim 3 , wherein the co-catalyst is selected from at least one of methylaluminoxane, trialkylaluminum, and alkylaluminium halide. 
     
     
         5 . The catalyst according to  claim 3 , wherein a mole ratio of metal element in the main catalyst to aluminum element in the co-catalyst is 1:(50-1000). 
     
     
         6 . The catalyst according to  claim 5 , wherein the mole ratio of the metal element in the main catalyst and the aluminum element in the co-catalyst is 1:(100-500). 
     
     
         7 . A copolymerization method of ethylene and methyl methacrylate, adopting the catalyst according to  claim 1 . 
     
     
         8 . The copolymerization method according to  claim 7 , wherein the copolymerization method comprises: subjecting ethylene and methyl methacrylate to a copolymerization reaction under a catalysis of the catalyst;
 a pressure of the copolymerization reaction is ≤10 MPa, and a temperature of the copolymerization reaction is ≤100° C.   
     
     
         9 . The copolymerization method according to  claim 8 , wherein a solvent of the copolymerization reaction is selected from at least one of toluene, n-hexane, dichloromethane, and dichloroethane. 
     
     
         10 . A copolymer of ethylene and methyl methacrylate, wherein the copolymer is prepared by the copolymerization method according to  claim 7 , and has a weight average molecular weight of ≥1×10 5  g/mol.